Problem:
The last day of the school year was a Wednesday. Students then have a 77-day summer break. On what day of the week will the next school year start?
It will be wednesday as well.
Why??
Well, "Wednesday was the last day of the school year" The start of the school's new year is after 77 days.
Now let's calculate it in weeks instead of days
77/7 (Because there are 7 days in a week) =11 weeks
We are already on wednesday...after 11 weeks it is going to be wednesday.
Assume wednesday is the 4th day of the week, 4*11=44 day ( must be also wednesday)